Alzheimer's disease Alzheimer's disease is an irreversible and progressive disease of the brain that slowly destroys memory and thinking skills, and eventually, to the ability to perform simple tasks. In most of those affected with the disease, symptoms first appear after age 60. Alzheimer's is the most common cause of dementia in the elderly. Dementia is the loss of cognitive functioning, is, thinking, remembering and reasoning, to a degree that interferes with daily life and activities of a person. The calculated figures vary, but experts suggest that the number of people suffering from this disease can be as high as 5.1 million Americans. The disease is named after Dr. Aloes Alzheimer. In 1906, Dr. Alzheimer noticed changes in brain tissue of a woman who had died of an unusual mental illness. Her symptoms included memory loss, language problems and unpredictable behavior. After she died, Dr. Alzheimer examined her brain and found several lumps (now called myeloid plaques) and twisted bundles of fibers (now called neurofibrillary tangles). The plaques and tangles in the brain are two of the main features of this disease. The third characteristic is the loss of connections between nerve cells (neurons) and the brain.Changes in the brain in Alzheimer's disease Although we do not know what initiates the process of Alzheimer's disease, we know that brain damage begins from 10 to 20 years before a problem becomes evident. The balls begin to develop in the deep part of the brain in an area called the endocrinal cortex, and the plates are formed in other areas. As more and more are forming plaques and tangles in particular brain areas, healthy neurons begin to function less effectively. Then they lose their ability to function and communicate, and eventually die. This damaging process spreads to a nearby structure called the hippocampus, which is essential in memory formation. As you increase the death of neurons affected brain regions begin to shrink. When approaching the final stage of the disease, the damage has spread widely and brain tissues have shrunk considerably.